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Operating with ARGUS-UMS UMS100/120/120 System Manual
37 3030.3059.72-02.00
2.3.3 Getting an overview of the spectrum using Scan
For a quick look at the frequency spectrum, such as after an alarm, use the <Scan> function. Select the
start and stop frequency according to the areas of interest. The increments (step width) are oriented to
various criteria.
The smaller the increment, the slower is the scan. Alternatively, in the display there are small
increments for a higher resolution. In this way, signals can be detected that are very close to one
another. However, this can be restricted by the resolution of the screen you are using. Generally, the
ratio between the selected IF bandwidth and the increment is important. However, you can overlook this
ratio, as the
Detector is generally in a max. peak position. Each signal is then displayed, even within
larger increments. The strongest signal determines the level value of the increment.
Here you are asked to develop suitable parameters for the signals which are of particular interest to
you.
Some examples for various parametrizing, for a better visualization of the time sequence with switched
on 2D waterfall diagram (for further information please refer to chapter 2.3.4):
• The highest possible speed for a large frequency range (Figure 2-6)
• The highest possible resolution for small frequency ranges, such as in the channel grid used - here:
analogue trunked radio, downlink - or GSM CHH downlink and the highest resolution (100 Hz) for
modulation analysis (Figure 2-7)
Figure 2-6: Example of a fast scan for a wide frequency range